You can decide to take the plunge and replace your current OS with the Mojave Public Beta. But it’s probably a bit risky. Here’s how to take advantage of the new without risking losing everything.
What’s new in macOS Mojave catches your eye but, problem, you only have a Mac and can’t afford to install a beta as your primary operating system? No problem, it is possible to reconcile the spirit of adventure of the beta tester and a certain peace of mind. How? ‘Or’ What ? By creating a second dedicated partition on your Mac, on which macOS Mojave will be installed.
Prepare your Mac
Start by making sure your Mac is compatible with macOS Mojave. Indeed, unlike High Sierra, which was designed to run on the same Macs as Sierra, macOS Mojave is a little more demanding. The list of compatible Macs is therefore a little shorter. Before you start an installation attempt, make sure that your machine is listed in the table below.
As every time you embark on an activity requiring to modify the structure of volumes and partitions on your storage drive, remember to back up your data first. You can use Time Machine, for example, or just copy the most important items to a hard drive or directory in the cloud.
Do you think you are ready? There is one last little thing to check: the amount of free space on your primary storage. To make a point (and possibly a little cleaning, here is what to do.
- Click on the menu Apple from the Finder menu, then choose About this Mac. A window opens and displays the contents of the tab Overview.
- Using the mouse, go to the tab Storage. Give your computer some time to take stock.
In a wonderful world, it would be necessary to be able to allocate between 40 and 60 GB at least to the secondary partition. 40 GB (or a little less) if you plan to use macOS Mojave very little and 60 GB if you plan to try switching to this partition to work on it regularly. This means that you obviously have to free up a little more space so that the main partition is not full.
If you’re over 60 GB free, good news, you don’t have much to do. On the other hand, if you run out of space, click on the button To manage to the right of the interface.
A window then displays more information. You can then take a look at the details of installed applications, messages and emails received, digital books, etc. in terms of gigabytes.
Before embarking on major maneuvers, you can start by emptying your trash … and then activate the option Optimize storage which will empty the disk space qualified as “purgeable”.
These are usually iTunes videos that have been downloaded and already watched but not deleted, for example. This can free up a lot of space.
Then try to sort through the Documents and possibly the applications. Two large workstations consuming storage space. In any case, it’s up to you to clean up what can be deleted.
Forward to the score
Once everything has been saved in independent storage and the necessary space has been cleared, it is time to get to the big job. The good news is that Apple has built a storage device management tool into macOS. It’s called Disk Utility.
1 / Find and launch Disk Utility
Let’s start by launching the tool.
- Click on the Finder icon in the Dock, then in the window that opens, go to Applications.
- Then find the folder Utilities. Disk Utility is waiting for you there. Launch it by double-clicking on its icon.
If you want to go faster, turn on Spotlight and start typing Utility. The application will be quickly found, validate the choice. The program starts.
2 / Create the score
Now is the time to get down to business. You will use Disk Utility to create the partition where macOS Mojave will be installed.
- In the Disk Utility interface, click the button Partition, at the top of the window.
If your computer uses macOS High Sierra and has an SSD, the file system used should be APFS. In this case, a menu is displayed offering you to add a volume or to partition the disk. If you are on HFS +, the proposal should be simpler.
- Either way, choose Partition.
- A third interface is displayed in turn. Click the + button. A new partition will then appear in the visualization of your disk space.
- In the input field name, type in a clear designation. For example, macOS Mojave.
We recommend that you then leave the file format determined by default, especially if it is APFS.
- Finally, you can choose to leave it the size assigned by default or to restrict it a bit by entering a new number in the field. Cut.
However, we do not recommend that you increase the space allocated by macOS from the outset. Keep in mind that you have to save space for the two OS that will coexist on your Mac.
- When you are satisfied with your settings, click the button. To apply.
- A dialog box warns you that a partition will be added and that your main partition, a priori called Macintosh HD, will be resized. Click on Partition.
- A final warning appears, read it carefully, then click To continue. Finally, be patient, as the operation may take several minutes.
3 / Download and install macOS on this partition
Now that the partition is created, you’ll move on to downloading and installing macOS Mojave.
- Go to Apple’s beta test site: beta.apple.com. Identify yourself either with the account you already have, or by creating an account.
- Then go to the page dedicated to macOS: here.
- Go directly to step 2 and click the Download macOS public beta access utility button. The download will start. It shouldn’t last very long.
As the link indicates you did not grab the beta itself, but a tool that will allow you to do so from the Mac App Store.
Now let’s install the utility.
- On your Mac, go to the directory Downloads.
- Then double click on the .dmg image to open it. Start the installation of the … macOS installer by double-clicking.
- Now that you have macOSPublicBetaAccessUtility installed, head over to the Mac App Store to download the beta itself. For this step, you will need a little more time. The file weighs approximately 6 GB.
If all goes well, as soon as the file is on your hard drive, the installation interface opens. If not, you can click the Open button in the Mac App Store interface.
- In front of the installer, you must now choose the target of the installation. Under the main volume icon (Macintosh HD), click Show all disks.
- Then choose the partition you created, in this case macOS Mojave.
Then click on Install. Wait a few minutes then when the installer is ready, validate one last time to restart the machine and start the installation itself. Let’s go !